<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>延时定时器</title>
</head>
<body>
    <script>
        //书写一个定时器
        setTimeout(function(){
            console.log('执行一次')
        },1000)//该1000ms
    </script>
</body>
</html>